Variable volume rotary vane pump



A. E. RUQNA VARIABLE VOLUME ROTARY VANE PUMP Feb. '28, 1950 2 Sheets-Sheet 1 Filed Oct. 18, 1946 /wwzww Patented Feb. 28, 1950 I UNITED? OFFICE I l 2,498,826 t,

VARIABLE;YOI2UME 'ROTARYI'VANE'PUMII" Arthur Ernest'Buona, Fairfax; Minn. A pplication qctoherI8, 194's Serial- No: 704,121

This invention relates: to-rotary pumps of'the single or plural reciprocating vane type. Said vide a mechanism of simple design and construetion for the control of the fluid volume discharge,

manually or automatically, of rotary'pumps, thus eliminating the necessityof the -conventional bypass valve system or volume relief valves :usedjin conjunction with rotary pumps.

some ('01. 1o2 120) the outer endsofwhich are beveled, substantially as shown at 2|, and conform to the. arc. oi'the: innerperiphery 1-5 of the-casing: I.

invention eliminates the normal proce dure. of throttling pump: discharge valves which creates a back pressure inthe pump and-con'sequently'a power loss: in that excesspower-is re-- quired to operate a. rotary pump undensaidiback' c pressure in relation tothe volume. output.

Other objects and advantagesloi my inventionwill be apparent from the following description and claims taken in conjunction with the attached drawings wherein like: parts are indicated by the, referencev characters-and; iIZuWhiCl-t';

Figure ,1 is a sectional view-oi-the invention taken approximately along the vertical. center line 2-2 of Figure 2.

Figure 2: is a vertical sectional-view of atypical rotary pump embodying my invention.

Figure 3 is a' fragmentary side elevational view of the rotor showing the cam. control shaft.

Figure rise fragmentary side-view of? the van showing the beveled edge. and the}. cam, follower pins;

The device of my invention consists of a hollow pump casing or stator lof generally circular configuration equipped with a suction and a discharge port, 4 and 3, respectively located at respective ends of the crescent-shaped power chamber 5, and comprises two separable heads 6 secured together by means of stud bolts 1. The casing heads have bearing recesses therein in which are disposed anti-friction bearings 8 cccentric with the cylindrical interior of the casing I and in axial alignment with each other in which the rotor 2 is concentrically journalled.

Vane-receiving slots 13 are provided in the main body of the rotor. Each of these slots has 2: a reciprocating pistonor" vane Maimounted there Said: vanes; are; generally: oblong: in shape;v

The inner terminals ofthe vanes are equipped with pinsor cam folio.wersz: [:62 which protrude through. the; ends of the rotorandu areguided: bythe: cams:

helical springs" [85 which encircle vane mounting? pinszilS; and impinge against: the inner ends-pf the vanes to'lforce the outer ends of said vanes: against the. inside periphery I of: the pump'casing i The cams tl 'are rotatably mounted in the hole low rotor 23 concentrically therewith and have:

respective, eccentric, circular recesses therein which receive. the corresponding vane pins t6; the pinsbeing. held in contact with they annular walls of these recesses by the: aforementioned helicalsprings: I 8; The springs. l8 are supported atstheir inner ends on shoes 28 whichbear: on

control shatt; If I Thee cams; H are secured in, spaced-apart re tending out ot'the. pump casing on the side of the: latter opposite: therotor, drive shaft 9. Grommets 2.3 of suitable packing material surround: the: shaft at opposite ends of the rotorand actagsealing rings: and an operating handle this secured on the outer end of this shaft outside-"0 f thepumpr casing. The cam control shaft is' journaled inv anti-friction bearings: 24; and

when in operation, the rotor. rotates around this" shaft in a counter-clockwise direction-as indicatedz'by thearrow 256 1 adjacent to Figure 2.

Referring particularly to Figure 2; with. the cams in the position therein illustrated, the intake stroke of the pump is from point 20 adjacent the inlet passage 4 to point 22 which is diagonally opposite a point midway between inlet passage 4 and outlet passage 3 and at which the rotor 2 contacts the inner wall of casing l. The compression or discharge stroke of the pump is from point 22 to a point Is adjacent the outlet fitting. In this case each vane contacts the internal casing wall throughout each entire revolution of the rotor, the discharge stroke is substantially equal in length to the intake stroke, and the capacity of the pump is at the maximum.

If shaft H and cams I! now be rotated from the position shown in Figure 2 in a counterclockwise direction or in the same direction as that in which the rotor 2 rotates, the vanes will be held out of contact with the inner wall of the casing until their ends have passed the point 22 thereby shortening the discharge stroke of the pump and reducing the pump capacity. The pump capacity can thus be manually regulated between maximum and zero by rotating shaft H and cams I! through an angle somewhat less than 180 in the direction of rotor rotation.

It is apparent from my foregoing description that this variable volume pump is dependent upon the cam mechanism so controlled by a shaft, and the vane mechanism with its controlled are power or compression stroke. The cams embodied in this invention may be placed at either or both ends of the rotor.

It is to be understood-that a rotary pump as set forth in this specification merely serves as an illustrative example, as such a device may be embodied in engine fluid drives under suitable conditions, etc.

It is apparent that many modifications and changes can be made without departing from the spirit of my invention, and therefore I do not Wish to limit my invention to the specific examples set forth in this specification.

What I claim is:

1. In a rotary pump having a hollow casing provided with a cylindrical inner Wall and closed ends, and an inlet and an outlet passage extending through the wall thereof, a hollow cylindrical rotor smaller than the hollow interior of said casing eccentrically journaled in said casing to contact said interior casing wall between said inlet and outlet passages and having radiallyextending, angularly-spaced, longitudinal slots therein, vanes slidably mounted one in each of said slots, and spring means urging said vanes outwardly of said rotor to resiliently maintain the outer edges of said vanes in contact with said casing inner wall, capacity adjusting means for said pump comprising a shaft extending concentrically through said rotor and journaled in said casing, a handle on one end of said shaft outside said casing, a pair of cams secured on said shaft and positioned Within said rotor, one at each end of the latter, each of said cams having an eccentric circular recess therein, and means on the inner edge of each vane extending into said circular cam recesses whereby the outer edges of said vanes may be held out of contact with said casing inner wall at the beginning of the pump discharge stroke by rotating said cams in the direction of rotor rotation, to shorten said intake stroke and thereby variably reduce the capacity of the pump.

2. In a rotary pum having a hollow casing provided with a cylindrical inner wall and closed ends, and an inlet and an outlet passage extending through the wall thereof, a hollow cylindrical rotor smaller than the hollow interior of said casing eccentrically journaled in said casing to contact said interior casing wall between said inlet and outlet passages and having radiallyextending, angularly-spaced, longitudinal slots therein, vanes slidably mounted one in each of said slots, and spring means urging said vanes outwardly of said rotor to resiliently maintain the outeredges of said vanes in contact with said casing inner wall, capacity adjusting means for said pump comprising a shaft extending concentrically through said rotor and journaled in said casing, a shaft'rotating handle on one end of said shaft outside of said casing, and cam means on said shaft within said rotor operatively engaging said vanes to adjustably vary the length of the discharge stroke of said pump upon rotation of said shaft by withdrawing the outer edges of said vanes from said casing inner wall at the beginning of the pump discharge stroke of each vane.

3. In a rotary pump having a hollow casing provided with a cylindrical inner wall and closed ends, and an inlet and an outlet passage extending through the wall thereof, a hollow cylindrical rotor smaller than the hollow interior of said casing eccentrically journaled in said casing to contact said interior casing wall between said inlet and outlet passages and having radiallyextending, angularly-spaced, longitudinal slots therein, vanes slidably, mounted one in each of said slots, and spring means urging said vanes outwardly of said rotor to resiliently maintain the outer edges of said vanes in contact with said casing inner wall, capacity adjusting means for said pump comprising a shaft extending through said rotor and journaled'in said casing, and cam means on said shaft operatively engaging said vanes to control the contact of the outer edges of said vanes with said casing inner wall upon rotation of said shaft.

ARTHUR ERNEST RUONA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS France July 12, 1939 

